Model # R20841-24
Power Blast Cal Shock 65 is 68% Calcium Hypochlorite with 65% available chlorine. Our best selling shock treatment, Cal Shock 65 is in a fast dissolving granular form so it quickly destroys organic waste, algae and bacteria saving you time and money.
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Is this shock safe for my above ground pool?
Hello Robert - This shock is safe for your above ground pool. We would recommend dissolving the shock in a bucket of water before it is poured into the pool.
Will this shock increase my pH level? I need a shock that wont.
Any chlorine based shock will increase the pH. The only type of shock that will not, is a non-chlorine based shock: http://www.inyopools.com/Products/22300006058120.htm
Do you carry swimming pool shock that is 100% calcium hypochlorite?
Unfortunately due to how unstable calcium hypochlorite is, there is no such thing. Our Zappit shock is one of the strongest on the market.
I think I have a chlorine lock in my swimming pool. How did I get it and how can I get rid of it?
Chlorine lock is a condition in your swimming pool when the chlorine levels ( free chlorine and total chlorine) are not the same which makes the chlorine useless. You can read more here.
What type of shock should I use in a bromine swimming pool?
If you are using bromine, you will want to use a non-chlorine shock. The non-chlorine shock will help sanitize the water through oxidation.
Is there any way to prevent hair from turning green in the swimming pool.
The best way to prevent this is to treat for metals on a regular basis. Metal free can be used as part of your regular maintenance.
I shocked my swimming pool and it turned green shortly afterward. What would cause that?
The change in color likely stemmed from the chlorine shock oxidizing the metals in your swimming pool. You can use this how to guide to get your swimming pool clear again.
My swimming pool is clear but when my kids and I went swimming, our eyes burned. My neighbor came by and checked and said that the pool should be fine because he can smell the chlorine. What is wrong with my pool?
It sounds like you have chloramines. Chloramines are formed any time ammonia and nitrogen are in the water. Chloramines smell bad and cause skin and eye irritation. You can resolve the problem using this method.
I keep the chemical levels (pH, alkalinity, calcium hardness, cyanuric acid and chlorine)in my pool within range but the water just doesn't seem right. Am I doing something wrong? Is there something I am missing?
I noticed you didn't mention your phosphates. I would recommend checking the phosphate levels and using a phosphate remover as needed.
Why do I need to shock the pool if I use chlorine tablets?
Chlorine tablets alone are not enough to keep the water sanitized. Pool shock helps to oxidize the water as well as breakdown chloramines.
My pool company uses liquid shock in my pool. Is this granular shock any better?
Yes. If you look at the labels of both products, you will find that liquid shock is weaker. The bottle has vented caps (to vent chlorine gas) so the longer it sits on a shelf, the weaker it gets. Granular shock is a lot stronger and does not lose its strength as long as it's stored properly.
No matter how much chlorine shock I put in my pool the chlorine level is always low. What can I do?
I would first make sure that you are testing the total chlorine AND free chlorine. If they are not the same reading, you may have a chlorine lock. If the chlorine levels are the same, I would check the pH, alkalinity and cyanuric acid levels.
I have an in ground vinyl swimming pool and usually use liquid shock. I have heard that the granular shock is better but it's not for vinyl pools. Is there another type of shock that I can use that is stronger than the liquid?
You can use the granular shock but I would recommend adding it to a bucket of pool water to pre-dissolve it then pouring it along the perimeter of the pool.
I tested my chlorine levels and they were at 0, so I shocked it. This didn't bring the levels up at all. What could be the problem and what should I do?
If your chlorine level remained at 0 after shocking, I would recommend checking the pH, alkalinity and cyanuric acid levels. I would also recommend checking the available chlorine percentage on the pool shock.
I'm looking for pool shock to sanitize my drinking water. Will this work?
I have heard of people using pool shock to sanitize drinking water but I can not promote the use of any pool shock for this purpose. You will want to contact the NSF for further information.
(5 out of 5 stars) Works great at a great price
Reviewed By: Noah R. from fort lauderdale ()
Pros: Works well, dissolves fast, good price
This is a great low price for 68% Cal Hypo. It dissolved fast and works great. I sometimes skip shocking my pool because of the price of shock or because I've run out. After getting 2 boxes of this shock I'm sure my pool will be looking better than ever.
(3 out of 5 stars)
Reviewed By: dnpcov from Vacaville, CA ()
FYI, when I received the order it was delivered in a crushed box. The contents were scattered all over and not very secure. Good pricing, good product, Very poor shipping Also, I did not receive the Cal-Shock 65 product which I used last year. I received "Zappit". I am hoping it will perform the same.
(4 out of 5 stars) Good product but not that price competitive
Reviewed By: David G. from Houston, TX ()
Pros: Ease of ordering. Shipping is slightly more than sales tax locally.
Cons: Not price competitive for an on-line product.
Works as well as anything I've bought at retail but I've since found comparable products on sale locally for the same or less.